Surgery obstructions from Khovanov homology

  title={Surgery obstructions from Khovanov homology},
  author={Liam Watson},
  journal={Selecta Mathematica},
  • Liam Watson
  • Published 9 July 2008
  • Mathematics
  • Selecta Mathematica
For a 3-manifold with torus boundary admitting an appropriate involution, we show that Khovanov homology provides obstructions to certain exceptional Dehn fillings. For example, given a strongly invertible knot in S3, we give obstructions to lens space surgeries, as well as obstructions to surgeries with finite fundamental group. These obstructions are based on homological width in Khovanov homology, and in the case of finite fundamental group depend on a calculation of the homological width… 
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